Check that component is enabled before attempting to disconnect pledge payments from Failed / Cancelled contributions.
CRM_Contribute_BAO_ContributionSoft::processSoftContribution($params, $contribution);
if (!empty($params['id']) && !empty($params['contribution_status_id'])
+ && CRM_Core_Component::isEnabled('CiviPledge')
) {
self::disconnectPledgePaymentsIfCancelled((int) $params['id'], CRM_Core_PseudoConstant::getName('CRM_Contribute_BAO_Contribution', 'contribution_status_id', $params['contribution_status_id']));
}